Despite the hard facts of racial discrimination and slum living in the United States, the shocking contrast in the material conditions of life between the masses of the poor and the privileged few in underdeveloped areas seldom fails to jolt the visiting American. Although the visitor is usually protected from the more distressing evidences of long-standing and rigid social stratification in the host country, he is almost sure to feel a lurking sense of guilt at the same time that he experiences the new gratifications accompanying the expansion of personal services and deferences bestowed upon him in the new setting. The public opinion pollster is familiar with the concept of class; he routinely anticipates and seldom fails to find differences in poll responses according to socio-economic level. But implicit in the whole concept of largescale opinion polling is the notion of an informed and thinking public whose opinions have relevance for policy decisions of one kind or another. More important, perhaps, is the underlying premise that every man's opinion has some worth and that every man has the right to be heard. The pollster often seems bent as much on proving that all men do have something to say on most issues as on simply investigating opinions. There has been reluctance to accept the fact of an inert public with respect to some issues, notwithstanding poll evidence revealing broad sectors of apathy and ignorance even in socalled advanced countries. Survey research in new areas, characterized by persisting patterns of sharp social differentiation, has strained to achieve national sampling almost as a goal in itself. In spite of the extremely high cost of field work in remote and isolated towns or semi-rural areas and despite the repeated experience of finding total ignorance regarding all but the most parochial concerns among such respondents, the tendency has been to stretch budgets to the limit in order to achieve breadth of coverage rather than to explore ways in which knowledge of the social structure and the flow of communications can be used to supplement survey research methods.